With a wrist-type blood pressure measurement apparatus, in order to correctly measure the blood pressure, measurement needs to be started when the height of the wrist to which the cuff is attached and the height of the heart are approximately the same. For this reason, various methods for matching the height of the wrist and the height of the heart have been proposed in the past (e.g., see Patent Documents 1 to 4).
Patent Document 1 discloses a blood pressure measurement apparatus according to which, on the premise of a usage mode in which a measurement subject performs attachment of a blood pressure meter to his or her wrist while his or her forearm is on a table and thereafter raises the height of the wrist by lifting the forearm from the elbow, the distance between the wrist and the heart of the measurement subject is measured by a sensor, and the height of the wrist is determined based on the distance.
Patent Document 2 discloses a blood pressure measurement device that uses the forearm roll angle and pitch angle to determine the height of the measurement site.
Patent Document 3 discloses a blood pressure measurement device that, by starting blood pressure measurement while the measurement site is in contact with the chest, allows blood pressure measurement in a state in which the heights of the measurement site and the heart match.
Patent Document 4 discloses a blood pressure measurement apparatus that determines the suitability of the blood pressure measurement based on the orientation of a user detected by a biaxial acceleration sensor and performs notification of the determination result.